1. Field of the Invention
The present invention relates to a device for heating passenger compartments or the like, especially in buses. The device includes a housing that has air inlet openings and air outlet openings and that accommodates a heat exchanger and a fan. The opening of the delivery conduit of the fan is offset relative to the inlet side of the heat exchanger, which is disposed downstream of the fan.
2. Description of the Prior Art
With a known device of this general type, the housing has air inlet openings in the vicinity of the drive motor, air flows axially through a fan wheel, the inlet side of the heat exchanger is disposed parallel to the plane of rotation of the fan wheel, and the end face of the housing is provided with air outlet openings. In addition to the fact that the axial fan has a relatively low efficiency, as a result of which the fan wheels have to be appropriately larger, dead corners result on the inlet side of the heat exchanger; it is not possible to assure that these corners are uniformly filled, and the airstream furthermore swirls greatly in these corners. The in-flow velocity at the air inlet openings is fairly high, so that the heretofore known device is not suitable for use, for example, in the floor region of the passenger area of a bus, since too much dust and debris would be drawn from the floor and into circulation with the air flow. This leads to premature fouling or clogging of the fan and the heat exchanger. In addition, there is the danger of a short circuit in the air flow between the air inlet and air outlet openings of the housing; this could lead to overheating and damage to the device.
Therefore, an object of the present invention is to design a device of the aforementioned general type in such a way that there can be achieved a great air capacity accompanied by a compact construction and little development of noise.